Rendell was best known for thrillers that delved into the criminal mind as well as the long-running television series based on her work, "The Ruth Rendell Mysteries".
Gail Rebuck, chair of her publisher, Penguin Random House, described her as "an insightful and elegant observer of society, many of her award-winning thrillers and psychological murder mysteries highlighted the causes she cared so deeply about."
Her best-known fictional creation, the sensitive Chief Inspector Reginald Wexford, featured in her first novel "From Doon to Death" (1964) and was a constant character in her work until she retired him in "The Vault" in 2011.
"I don't get sick of him because he's me. He's very much me," Rendell told The Guardian newspaper not long before she fell ill.
"He doesn't look like me, of course, but the way he thinks and his principles and his ideas and what he likes doing, that's me. So I think you don't get tired of yourself."
- Political campaigner -
Rendell started out as a journalist, writing features for a local paper near London, the Chigwell Times, but was forced to resign after reportedly inventing stories.
Her first published novel came about almost by default -- she submitted a comedy of intrigue to a publisher who did not like it and asked if she had anything else.
So she gave him the manuscript of a Wexford detective story which was gathering dust in a drawer and it was published.
Firmly on the political left, she was a major donor to Britain's Labour party and was made a life peer in 1997 by the then prime minister Tony Blair.
As Baroness Rendell of Babergh she became a very active "working peer" in the House of Lords, introducing a law that stiffened the penalty for female genital mutilation and making it illegal for UK nationals to perform the practice abroad.
Strongly opposed to Scottish independence, she was one of 200 prominent British people to sign a plea to Scots to stay within the UK before last September's vote.
She said she wrote her novels in the morning, limiting herself to four hours' work, and in the afternoon sat in the upper house of parliament, going through draft laws and debating government policy.
She was a close friend of fellow novelist and peer P.D. James, who died in 2014 at the age of 94.
Following her stroke in January, Jean-Claude Berline, the French editor of her next book, said that after James's death, Rendell was "the last grande dame of the police thriller".
She was awarded four Gold Daggers and a Diamond Dagger from England's prestigious Crime Writers' Association, as well as three Edgar Awards from the Mystery Writers of America among many other accolades.
As well as the TV series that carried her name, Rendell's novels were also adapted for the big screen by some of the biggest names in cinema, including the Spanish director Pedro Almodovar who shot "Live Flesh" and French film-makers Claude Chabrol and Claude Miller.
Rendell said she drew her talent for suspense from a studious love of literature.
"I think one looks at great fiction and sees how that is done. Think about Emma," a novel by 19th-century author Jane Austen, she told The Guardian.
"We know there's something strange about Jane Fairfax, but it's not until very far on that we realise that all the time she's been engaged to Frank Churchill. There's nothing clumsy about it, nothing appears to be contrived, and it's done by withholding," she said.